Mercury – Oil Pressure Gauge | Dual Scale | Gray Face | 2-1/8" (52 mm) | 79-8M0065974Mercury Oil Pressure Gauge Dual Scale Gray Face 2 1 8" (52 mm) 79 8M0065974 Overview The Mercury Oil Pressure Gauge (79 8M0065974) gives you an accurate, real time reading of your engines oil pressure so you can stay ahead of maintenance and protect your motor. It features a dual scale display that shows both PSI and Bar, letting you monitor pressure in either English or Metric units. The gray face, white numerals, and glass lens provide a clean,